Author Topic: Ideas for larger payload orbital delivery  (Read 2149 times)

Offline scott taylor

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Ideas for larger payload orbital delivery
« on: 12/09/2007 01:25 PM »
An idea for large payload orbital delivery:
1.   Adapt shuttle type vehicle to carry 100-ton payload.
2.   Adapt main fuel tank to carry more fuel and correspondingly less oxidizer.
3.   Synchronize launch with large ocean based pre-accelerator (see www.hypacc.com ).
4.   Loft scramjet powered drone-carrying remainder of required oxidiser.
5.   Drop solid boosters in usual fashion.
6.   Dock oxidizer drone with shuttle (Ok, very tricky but possible in very thin atmosphere)
7.    Continue journey to orbit/ISS
8.   Repeat several times.
9.   Build space ship.
10.   Go to Mars!
I have built some very small models of my original Hydro Pneumatic Accelerator (HYPACC) and some models that demonstrate a column of water will effectively drive a pump gun (Hydro Pump Accelerator. HYPACC 2). the aim being to reduce the engineering costs and eliminate the recoil issues of up-scaling the SHARP light gas gun.
Click the animations button to see HYPACC 2 in motion or the archive button to see the original idea.

Offline Jim

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RE: Ideas for larger payload orbital delivery
« Reply #1 on: 12/09/2007 01:28 PM »
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scott taylor - 9/12/2007  9:25 AM

6.   Dock oxidizer drone with shuttle (Ok, very tricky but possible in very thin atmosphere)


Not tricky but impossible

Offline scott taylor

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Re: Ideas for larger payload orbital delivery
« Reply #2 on: 12/09/2007 02:01 PM »
what would make such a manouver impossible? I am sure the same thing was said about in-flight refuelling but British Aerospace were obviously not listening!

Offline Jim

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Re: Ideas for larger payload orbital delivery
« Reply #3 on: 12/09/2007 02:06 PM »
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scott taylor - 9/12/2007  10:01 AM

what would make such a manouver impossible? I am sure the same thing was said about in-flight refuelling but British Aerospace were obviously not listening!

No it wasn't said.  In-flight refueling was done in the 1920's and is no big deal.

A launch vehicle takes less than 10 minutes to get into orbit. So when does it have time to loiter and take on propellants, not to mention linking up with another vehicle at speeds of over 5000 to 10000 mph?

Offline scott taylor

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Re: Ideas for larger payload orbital delivery
« Reply #4 on: 12/09/2007 03:22 PM »
Surely speed is relevant to atmospheric density.  It is almost certainly impossible to perform a high-speed link up using current public domain technology but surely the advances in missile defence technology and ESA’s planned unmanned linkup with the ISS show that it cannot be entirely impossible.

Offline Jim

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Re: Ideas for larger payload orbital delivery
« Reply #5 on: 12/09/2007 03:30 PM »
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scott taylor - 9/12/2007  11:22 AM

Surely speed is relevant to atmospheric density.  It is almost certainly impossible to perform a high-speed link up using current public domain technology but surely the advances in missile defence technology and ESA’s planned unmanned linkup with the ISS show that it cannot be entirely impossible.

Nope.  Not even in the non public domain.  

Missile defense involves placing object in the path of a missile.  The velocity differences are on the order of several miles per second, so not actually a "linkup"

The ESA ATV docking with the ISS is easy because both are IN orbit and not under thrust during ascent .   The first ATV flight has several days of testing before docking.  Subsequent flights will take a couple of days to reach the ISS

Offline Jim

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Re: Ideas for larger payload orbital delivery
« Reply #6 on: 12/09/2007 03:31 PM »
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scott taylor - 9/12/2007  10:01 AM

what would make such a manouver impossible? I am sure the same thing was said about in-flight refuelling but British Aerospace were obviously not listening!

here is no time to mess with docking during ascent. Setting up an aircraft inflight refueling takes longer than the whole shuttle launch

The drone would have to fly almost the same trajectory and therefore almost go into orbit to. Doing the refueling while the engines are burning would be foolish, due to leaks, plume interaction, etc.

Adding a "loitering phase" to a launch would just require more propellant, which negates the intent of the refueling

Also. The SRB's are jettisoned at over 150k ft and 3000 mph. Seconds later, the shuttle will be higher and faster than scramjets can achieve


Offline jimvela

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RE: Ideas for larger payload orbital delivery
« Reply #7 on: 12/09/2007 07:44 PM »
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scott taylor - 9/12/2007  7:25 AM
An idea for large payload orbital delivery:
1.   Adapt shuttle type vehicle to carry 100-ton payload.

Stop there, build a tube with an engine pod at the back and payload forward,  you have something like Shuttle-C, which IMHO wasn't too bad an idea.  

Or,  build Direct, or Ares V...

You get a heavy payload launcher, which might be an enabler for various missions.


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2.   Adapt main fuel tank to carry more fuel and correspondingly less oxidizer.
Terrible idea.  Leave the tank alone for commonality amongst your multiple launches, which you need anyway (see below).

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3.   Synchronize launch with large ocean based pre-accelerator (see www.hypacc.com ).
4.   Loft scramjet powered drone-carrying remainder of required oxidiser.
5.   Drop solid boosters in usual fashion.
6.   Dock oxidizer drone with shuttle (Ok, very tricky but possible in very thin atmosphere)

Impossible, impractical.
It's hard enough to get one launch off the ground on a specific timetable, let alone two.

Rendezvous, docking, and transfer at the altitudes, velocities, and acceleration/thrust levels seen late in a lower stage burn is not workable.

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8.   Repeat several times.
9.   Build space ship.
10.   Go to Mars!

Here's where the idea really falls apart for not seeing the forest for the trees.  

If you've got to send multiple vehicles up anyway, just have one vehicle payload carry propellants (e.g. a tanker system and fuel depot), while the others carry vehicle and mission payloads.

If you really want to drive down propellant costs, then maybe a high-risk, low-cost system could deliver propellant tanks for a tanker to get to a depot, but again there isn't any such system in existence yet.

If we ever get really serious about extraterran exploration, the orbital/interplanetary/deep space drives will be with high ISP / High power drives and the energy source will be non-chemical ( e.g. fission reactor and big ion drives with current state of technology, maybe fusion in the distant future).  

Chemical propulsion will still exist for those high-thrust events like entry, descent and landing.  

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I have built some very small models of my original Hydro Pneumatic Accelerator (HYPACC)

Some form of cannon/gun/linear accelerator/whatever that can fling a dense payoload into LEO is mildly interesting for flinging structural/raw material up- but that's a whole different concept.

Offline scott taylor

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Re: Ideas for larger payload orbital delivery
« Reply #8 on: 12/13/2007 12:27 AM »
The pump gun idea, like all direct orbital accelerators, has the same issue of atmospheric density cooking the payload (in-fact worse as it is at sea-level instead of on a mountain top) and the g-forces mashing it. The advantage of using water to drive a pump-gun is it could work on a really big scale. As a scramjet accelerator it may be cheaper than a maglev system for tough payloads and more practical than an orbit gun. To extend that economy to soft payloads it would be necessary to perform an in-flight link-up, way beyond the ability of today’s rocket scientists (apparently) so it would need to be employed as part of an ambitious project (such as a Mars mission) to justify a hard payload only capacity.   Still, all very mildly interesting (more like new socks than new ideas surely?)

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